Pump



Patented Apr. 1, 1930 UNI-TED STATES- PATENT OFFICE ROBERT W. ALLERTON,OF SOUTH ORANGE, NEW JERSEY, ASSIGNOR T WORTHING? TON PUMP A.NDMAOHINERY CORPORATION, OF NEW YORK;` N. Y., A CORPORATION OF VIRGINIArum? Application led August 12, 1924. Serial No. 731,539.

This invention relates particularly to that type of pumps used with hotliquids and is intended yespecially for use in'oil cracking processesand the like, in which oil is handled sat very high temperatures.l

The invention includes a novel forni of seal-- ing means; for the pumpplunger rod, by which injury to the packing by contacttherewith of theportion of the rod subjected'to contact with the hot oil in the pumpcylinder, and danger of the hot oil flashing and causing tire, areavoided, all leakage from the pump cylinder is avoided, and oil may besupplied directly to thecylinder and used for sealing, preferably beingmake-up oil for the system. For a'full understanding of the inventiona'detailed description ot a construction cmbodying the'invention in itspreferred form will now be given in connection with the accompanyingdrawings, andthe features forming the invention then be pointed out inthe claims.

In the drawings- 25 Figure 1 is a longitudinal section of a pumpequipped with the invention;

Figure 2 is an end view, looking to the right on the line 2-2 of Fig. 1,and y Figure Bis a` central longitudinal section plunger rod.

Referring to the drawings: The pump shown is of the type known as ablock pump formed from a single forged block of metal 20, the pump shownbeing a two cylinder or duplex pump, although this is not essential. Theblock 20 has bores forming the pump cylinder or chambers 21 in which aremounted the usual liners 31 in which move the plungers 26 operated byplunger rods 27. The suction and discharge valves (not shown) aremounted in valve bores 50 cutting the cylinders 21 and the suction anddischarge pas- Asages 22, 23. These valve bores are shown as closed byplugs 11: The yalves and their mountings may be of any suitable form.

Referring tothe parts especially embodying Y the'- invention, theplunger rods 27 run through stuffing boxes 28 which are of such lengthas to prevent the parts of the rods subthe oil thus supplied to thecylinder.

of the stuing box and sealing means for thel jected to contact with thehot oil in the pump cylinder from coming into' contact with theatmosphere or with thel packing, when the lungers are at the end oftheir strokes to the left in Fig. 1. Each box 28` starting from the pumpcylinder, encloses a sleeve 17 of suitable metal so formed as to providea small clearance between it and the plunger rod, anda metal lanterngland 14 between the sleeve 17 and packing 16 of any suitable form. Thechamber enclosing the rod 2T by the lantern glandl: connects with a pipe15 through which oil is delivered under pres sure to the rod chamber.The pressure of the oil supplied through pipe 15 in some cases may be inexcess of the highestpressure in the cylinder, but. as the pressure inthese oil cracking processes is quite high. it is economicalandpreferahle thatthe oil should be supplied to pipe 15 only under apressure slightly in excess of the suction pressure` so that oil williiow through the clearance between the rod 27 and the met-al block 17only during the and formed suction stroke. With the pressure on the oilthe return of the oil from the cylinder through pipe 15 under dischargepressure,and for this purpose a non-return check valve on pipe 15 willbe provided. As shown in Fig. 2, the pipes 15or the two cylinders areeach provided with. check valves 19 and these two pipes 15 are coupledtoa supply pipe on which is a hand valve 51, so that the supply of oil maybe regulated as desired. The stuffing box, or that portion of the boxbetween the packing and the cylinder, may be cooled by any suitablecooling liacket, if desired, so as to keep cold oil next the packing.

The oil supplied to the cylinders through pipes 15 may be taken from anypart of the system, the oil in'these cracking processes usually beingcirculated in a closed circuit, but preferably the oil will be takenfrom a source outside the circuit and in quantity such as to constitutethemake-up oil, to maintain the quantity of oil desired in the system,,and avoiding any other provision for adding make-up oil to the circuit.The quantity of oil fed to the cylinder may be fixed as desired by thesupply through pipe 15, the clearance of the plunger rod in the cylinderhead being less or more as required. It Will be under- 5 stood.yhowever, that any other provision for make-up may be used and the pipes15 not he used for the supply of make-up. With this construction therewill be no leakage of oil through the packing 16, the danger of fire dueto oil leaking past the stuing box is avoided, and the hot part of thepiston rod which is in direct contact with the hot oil in the cylinderis not exposed tothe atmosphere nor does it come in contact with thepacking. The flow of oil to the cylinder also acts to flush any coke orother small particles back to the cylinder and thus protects thepacking. The oil from the pump may be cooled, preferably by make-up oilto save the heat, and then used in the plunger-rod chamber.

It will be understood that various changes may be made in the details ofconstruction herein shown and described, While retaining the inventiondefined by the claims.

What is claimed is:

1. A pump for hot liquids having a chamber enclosing the plunger rodwith provision for flow of liquid from said chamber to the plnngerchamber, means for supplying liquid to said rod chamber under pressure,a non-return check valve for preventing the return of the liquid fromthe plunger chamber, and a valve for regulating the supply to the rodchamber.

2. A pump for hot liquids having a chamber enclosing the plunger rodwith provision for flow of liquid from said rodchamber to the plungerchamber, and means' for supply- 40 ing liquid to said' rod chamber underpressure in excess of the *pump suction pressure but less than the pumpdischarge pressure.

3. A pump for hot liquids having a chamber enclosing the plunger rodwith provision for How of liquid from said rod chamber to the plungerchamber, means for supplying liquid to said rod chamber under pressurein excess of the pump suction pressure but less than the pump dischargepressure, and a nonreturn check valve for preventing the return of theliquid from the plunger chamber.

In testimony whereof, I have hereunto set.

my hand. ROBERT W. ALLERTON.

